Might be an apple and oranges issue here. A couple friends of mine have 4x4 'burbs (3/4t w/ 454 and 1/2t w/350) both are early 90's vintage. Anyway, both went the chip route and are extremely happy. Both report more "seat of the pants" power and improved mileage. As part of this upgrade, both went with cat-back exhaust systems and lower temp thermostats.

iam pretty sure that is the chip i put in my 87 monte SS
305 / didn't do much...
i got it out of SUMMIT
you have to change the thermostat...
and drive on Super atleast 93 grade fuel
i never did...
i think i paid like $130.00 ????

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